Any one out there manage to re-dye faded seat embroidery?

So I came across a pretty nice set of Tobin seats that would really add to my bike rebuild/revamp but the pass pillion embroidery is pretty faded and the driver seat the embroidery is good but just not the color I would like.

I was thinking maybe fabric pens or something to dye them to royal blue but my concern is color seepage and/or the color coming off onto clothing. The driver embroidery is on the back of the cushion so I don't think that my bottom will even make contact with it but the pass seat is the whole seating surface. The girlfriend will likely hang my head out if I was to make here pants have a blue hayabusa kanji on the ass portion.